Let's Just Resign to the Fact That This Could Be Cute, OK?
Let's be honest with one another -- some people (ahem) give this here couple a hard time for being a strange and slightly icky couple, but there could be much, much worse things happening. This couple could be somebody like, I don't know, Shia LaBeouf and Madonna for example, and it might not necessarily get worse than that. Small favors are good things, and though John Mayer and Katy Perry aren't the very best of couples, they aren't the potential worst, either.
That ring up there, however, says a lot (?) about the state of John and Katy's relationship. For example, how they might be engaged? To, you know, be married? That could be a thing that ring is saying, and if that's what the ring is saying, then we can ignore the squickiness and concentrate on that beautiful emerald-looking ring. If it's not, we can all hold the collective breath we didn't even know we were holding and resign ourselves to the fact that if this isn't an engagement ring, there's likely to be one in the future anyway.
One way or the other, what a pretty couple and a pretty ring, huh?